Ultrafast response of third-order optical nonlinearity in glasses containing Bi_2O_3

We prepared nonresonant-type homogeneous glasses containing Bi(2)O(3) by the melting method. The thirdorder optical nonlinear susceptibility chi((3)) was found by third-order harmonic generation measurement to be 9.3 x 10(-12) esu. We attribute the nonlinearity of these glasses to the large molar refraction of glasses containing Bi(2)O(3). These glasses also exhibited an ultrafast response time below 200 fs by a degenerate fourwave mixing method using a femtosecond laser, indicating that the nonlinearity of these glasses originated mainly from pure electronic polarization.